This article identifies the determinants of political trust and its relationship with the support for regime in the relatively recent Latin American democracies. Based on the 1996 Latinobarometer data, the author analyses five hypothesis about political trust in five countries: Argentina, Brasil, Costa Rica, Colômbia and Chile. The results show that the preference for democracy, the conceptions about economy and satisfaction with the government, the optimism with the country and family futures, and the interest in politics are the main determinants of trust in political institutions.